• Wet nitrous setup testing on Rob Beck turbo upgraded N54 335i - 500 wheel horsepower

      We finally completed the nitrous install on my 335i. The power gains where phenomenal but as people know it is easy to get carried away. We found a medium result between boost and jet size and tuned the car to make 500whp at only 1 bar boost. We saw much higher numbers but at the moment until the gearbox is upgraded we will leave it at that. OB from Chip Logic work was meticulous both in terms of the wiring but also in terms of certain plumbing that was required to make the kit fit as best as possible. Below are some pictures with some explanations for those that are not familiar with nitrous.






      The tank on the left provides fuel to the fuel nozzle without affecting the cars normal fuel pressure. A must for high horsepower application. The fuel line, nitrous line and wiring disconnect under the carpet. I can then lift the whole matt and replace it with a second one for grocery purposes.






      The nitrous solenoids can be seen on the right corner of this picture.






      This is the purge valve for the nitrous. The pipes for this was custom as we wanted the purge to come out at the fog lamp area.






      Jet location with the jet in direct path of the intake manifold.
      My methanol nozzle is also visible but is not in use at this stage.






      The arming switch and purge switch, the rest is controlled by a progressive controller but we have installed as a extra safety measure a switch that allows the solenoids to active only if the overdrive button is pressed. That way I can go full throttle but only allow the progressive controller to do its thing when overdrive is pushed.

      Other than that there is nothing visible in the interior.






      The dyno printer was damaged but someone got a picture of one of our test runs in the early tuning stages, it also turned out the rpm was not set properly as the drop of point is 500rpm higher than it should be. Please keep in mind this was done at 5500ft. Base run on stock boost was 276whp and a average stock 335 makes under 250whp on this dyno. So the figures are comparitave to a Mustang dyno. No methanol was used for these numbers.
      This article was originally published in forum thread: Wet Nitrous and RB powered started by George Smooth View original post
      Comments 63 Comments
      1. klipseracer's Avatar
        klipseracer -
        Click here to enlarge Originally Posted by George Smooth Click here to enlarge
        At the moment in terms of fueling we in the safe level of what the stock system can give extra. At higher boost level we will have to go with a minimum .28 fuel jet. The spike you mention is evident and takes the initial AFR to 14's for around 200rpm. We avoiding purging at this stage to avoid this but its not really a train smash in my opinion. When I get the upgraded gearbox I will be going direct port and we will use the 2 stage method you mentioned through the NX controller. The extending of the nitrous line is also affective but we do not have the luxury of having a shop around the corner here in South Africa. Chances are the nitrous solenoid will stay in the existing place and the fuel solenoid will be close to the manifold.
        Thank you very much for the effort you have taken to put down your experience for every ones benefit. I am going to look at the WON solenoids and test out a set.
        Complete side note, I dealt a lot with clients in South Africa, and if you're doing all this modding and stuff then you must be BALLIN down there! Pretty sure the average annual income is somewhere around 12,000 USD.
      1. George Smooth's Avatar
        George Smooth -
        Click here to enlarge Originally Posted by klipseracer Click here to enlarge
        Complete side note, I dealt a lot with clients in South Africa, and if you're doing all this modding and stuff then you must be BALLIN down there! Pretty sure the average annual income is somewhere around 12,000 USD.
        Haha this is actually my wife's car for groceries. I am average here there is a lot of wealth her and poverty on the same note.
      1. Sorena's Avatar
        Sorena -
        Click here to enlarge Originally Posted by George Smooth Click here to enlarge
        Haha this is actually my wife's car for groceries.
        Huh, I should boost the girl's car too.
      1. Sticky's Avatar
        Sticky -
        Click here to enlarge Originally Posted by George Smooth Click here to enlarge
        Our next track day is on the 4th of September. Will be doing some testing to see if there is any benefit of using the methanol until then and if the gearbox arrives in time will be going with bigger jets. Lets see what happens. I do not expect to duplicate US numbers here but from what I have seen I stand a good chance of getting the 60-130 record even at this altitude.
        Are there no options around you for lower altitude runs?
      1. George Smooth's Avatar
        George Smooth -
        Click here to enlarge Originally Posted by Sticky Click here to enlarge
        Are there no options around you for lower altitude runs?
        590km away but got it planned to go. For now I am just aiming for 60-130 times until I pull the rear wider for traction off the mark.
      1. dzenno@PTF's Avatar
        dzenno@PTF -
        George any updates on this??
      1. George Smooth's Avatar
        George Smooth -
        Click here to enlarge Originally Posted by PEI330Ci Click here to enlarge
        George,


        One thing that's missing from your dyno graph is the AFR plot, specifically what happens when the nitrous system is activated. Do you have a lean spike? If so, how long does it last? I've used either a 2 stage controller with nitrous and fuel hooked up to different stages to "time" the activation point, and get rid of the lean spike electronically. The best scenario though is to put the fuel solenoid within inches of the discharge nozzle. I've played with running 8", 12", 18", and 24" nitrous lines after the nitrous solenoid, and found that the difference in activation delay was minimal, and that you get a lot better effect by keeping the fuel solenoid closer to the discharge nozzle. I personally prefer to "fix" an activation lean spike physically, rather than electronically.....
        I just wanted to say thanks about the staging of the solenoids. I ran the fuel on the second stage and activate it 100rpm prior to the gas and the lean spike is gone. I have also moved to NOS solenoids and am not pulsing anymore.
      1. dzenno@PTF's Avatar
        dzenno@PTF -
        Any new dynos George? Instead of pulsing do you just open the fuel and nos solenoids now? What're you using to set up fuel and nos activation?
      1. George Smooth's Avatar
        George Smooth -
        Click here to enlarge Originally Posted by dzenno Click here to enlarge
        Any new dynos George? Instead of pulsing do you just open the fuel and nos solenoids now? What're you using to set up fuel and nos activation?
        Not really interested in dynos, I have been doing testing on the road mostly just to check the AFR's. Am keeping the power around 500whp due to the gearbox. I am using the NX controller without any pulsing or ramp.
      1. dzenno@PTF's Avatar
        dzenno@PTF -
        What boost/timing/AFR are you running with it?
      1. Cn555ic's Avatar
        Cn555ic -
        When you were pulsing the solenoid for nitrous, did it also pulse the fuel solenoid too? How high was the lean spike that you saw when it happened?
      1. Cn555ic's Avatar
        Cn555ic -
        Also why not as a precautionary measure also inject some methanol into the intake track for some added security! It can't hurt and I would do it for sure
      1. George Smooth's Avatar
        George Smooth -
        Click here to enlarge Originally Posted by dzenno Click here to enlarge
        What boost/timing/AFR are you running with it?
        low 12's into 11's at the top.

        Click here to enlarge Originally Posted by Cn555ic Click here to enlarge
        When you were pulsing the solenoid for nitrous, did it also pulse the fuel solenoid too? How high was the lean spike that you saw when it happened?
        They on the same circuit so I guess it pulsed both. As PEI33ci mentioned the pulsing is not very accurate and on ramp up I was getting variable outputs on initial dyno testing.

        Click here to enlarge Originally Posted by Cn555ic Click here to enlarge
        Also why not as a precautionary measure also inject some methanol into the intake track for some added security! It can't hurt and I would do it for sure
        My methanol system was initially removed as I had the car set up to run with a flash tune hence to safety net. I am also hesitant with over fueling the car as it can cause major backfires in conjunction with the nitrous. I am not to phased with extra security, when I put the nitrous on I was prepared if the engine broke. Where I got caught out was I was expecting the gearbox to handle more, I am still planning to run a big jet for a 60-130 glory run.
      1. Cn555ic's Avatar
        Cn555ic -
        Good to know! I am also running low 12s- 11s on nitrous. Look forward to your glory runs!!
      1. dzenno@PTF's Avatar
        dzenno@PTF -
        George, how much boost and what timing?
      1. George Smooth's Avatar
        George Smooth -
        Click here to enlarge Originally Posted by dzenno Click here to enlarge
        George, how much boost and what timing?
        I run 16psi in the midrange and taper it down to 13 from 5500 and up. At 5000rpm the gas kicks in although I play around with it quite a bit. Timing starts stock like and tapers to 9 degrees. I can run more timing because of the altitude I am at.
      1. Cn555ic's Avatar
        Cn555ic -
        So you have nitrous kick in at 5100 and fueling kick in at 5000rpms?? If so why so late in the rpm band?
      1. George Smooth's Avatar
        George Smooth -
        Click here to enlarge Originally Posted by Cn555ic Click here to enlarge
        So you have nitrous kick in at 5100 and fueling kick in at 5000rpms?? If so why so late in the rpm band?
        The car makes enough torque in the midrange to break traction as it is. Besides once you start shifting you do not need the power that low. It also preserves the motor. If the gas came in sooner with the torque the RB's make I am sure it will bend the rods.
      1. Cn555ic's Avatar
        Cn555ic -
        Click here to enlarge Originally Posted by George Smooth Click here to enlarge
        The car makes enough torque in the midrange to break traction as it is. Besides once you start shifting you do not need the power that low. It also preserves the motor. If the gas came in sooner with the torque the RB's make I am sure it will bend the rods.
        I hear your reasoning but this is the first I have seen nitrous activation so high in the rpm band.. The norm I see is between 3000-6200, the meat of the rpm band..At what rpm do you have nitrous shut off?
      1. dzenno@PTF's Avatar
        dzenno@PTF -
        Click here to enlarge Originally Posted by George Smooth Click here to enlarge
        The car makes enough torque in the midrange to break traction as it is. Besides once you start shifting you do not need the power that low. It also preserves the motor. If the gas came in sooner with the torque the RB's make I am sure it will bend the rods.
        Would you adjust anything if you went down to sea level?